This project involves the injury and regenerative response of the nephron to a variety of toxic substances. The investigations are concerned with the normal structure and function of the tubular components of the nephron as well as their response to injury. Of primary interest are the transport functions, physical alterations and correlative ultrastructural aspects of the nephron following toxic injury and the subsequent regenerative response to this injury. BIBLIOGRAPHIC REFERENCES: Vera-Roman, J., Krishnakantha, T.P. and Cuppage, F.E. Gentamicin nephrotoxicity in rats. I. Acute biochemical and ultrastructural effects. Lab. Invest. 33:412-417, 1975. Cuppage, F.E., Setter, K.R. and Sullivan, L.P. Effects of chronic administration of gentamicin on the kidney. Amer. J. Pathol. 82: 56a, 1976. (Abstract presented at American Association of Pathologists and Bacteriologists, March, 1976.)